In the art of cooking, means may be provided for surrounding the food being cooked with a flavoring smoke which imparts to the food what is often referred to as a "barbecue" flavor. The barbecue flavor sought to be achieved in modern cooking appliances originated in open-pit cooking of a whole domestic animal such as a steer or pig. This cooking technique involved building a fire of hardwood logs, such as hickory, in a pit dug in the ground and mounting the carcass of the steer or pig over the pit by means of a spit which was rotated from time to time to achieve relatively even cooking of the meat. Many hours of cooking time were required and during this time the smoke generated by the burning logs would impart a particular "barbecue" flavor to the meat.
Efforts have been made in the past to achieve the same type of barbecue flavor with modern cooking appliances, especially outdoor grills burning either charcoal or gas. However, it is difficult to achieve the same barbecue flavor with such modern appliances because the fuel is different and much shorter cooking times are involved. Some of the past efforts in this field are described in the following paragraphs.
U.S. Pat. No. 4,190,677 issued to Robins suggests that barbecue flavoring may be achieved by placing a bed of wood flour upon a tray suspended over a bed of burning charcoal. However, the tray shields the wood flour and it is slow to ignite because the bottom of the tray must be heated to its ignition temperature. Woodchips would be even more difficult to ignite. On the other hand, the use of woodchips would be desirable in order to generate smoke for substantially longer periods of time.
U.S. Pat. No. 4,471,748 issued to Venable suggests suspending a tray of woodchips directly beneath a burning bed of charcoal fuel. In the arrangement disclosed here, there is no shielding of the woodchips and their direct exposure to the hot coals causes rapid incineration of the woodchips to ash. Such rapid burning allows very little time for smoke generation and requires frequent replacement of the woodchips.